Here are the pics of what I am seeing. This yeast has been through 2 APAs at 1058 and 1056, respectively). Tomorrow, I wanted to use this slurry to ferment a 1060 IPA and be done with it.

As far as extenuating circumstances...All that I can think of is this:

I was very-very careful to keep this yeast cool ... even using a swamp cooler at times.

The fermentation temp was 65f throughout the vigorous phase and it rode out another week or so at 63-64f (12 days total). I took gravity readings over several days to be sure we were done. It didn't budge from 1010 FG all week.

The day I racked to secondary (I needed that bucket and planned on dry hopping in another vessel), the ambient temp jumped up to close to 70f. The beer itself never made it past 68f...but I could see the yeast getting active again in the bucket (occasional stuff shooting up from the bottom to the surface).

Maybe fermentation was kicking up again causing that "special" flocculation?